National Crime Squad (NCS)officers issued an appeal for information on the whereabouts of Andrew Stephen Rogers from Maesteg, near Bridgend, who has disappeared from his home.
It follows the disappearance last week of Darren Owen from Cardiff Bay, who has more than a dozen warrants for his arrest outstanding on firearms, drugs and money-laundering offences.
Both men are wanted in connection with the anti-drugs initiative Operation Tarian, carried out by three Welsh police forces and the NCS, which recovered large amounts of drugs during raids over the summer.
Amphetamines, cocaine and cannabis as well as firearms with a total value of nearly £1 million were recovered.
Arrests made
Mr Rogers, who lives at Lansbury Close in Maesteg, is also known by his nickname "Tyson".
Det Insp Ian Haylock, of the NCS Wales branch, said: "We are keen to talk to Mr Rogers about a range of matters and are urgently seeking his whereabouts.
"We are sure that Mr Rogers already knows that we need to speak to him and I would personally urge him to get in touch with us.
"I have to stress that we are actively seeking him at the moment and will continue to do so until he turns up."
Six people were arrested in July and August in connection with the operation.
Officers had issued a warrant for Darren Owen's arrest when he fled.
Mr Owen is believed to have been living a luxurious lifestyle in Cardiff Bay
The NCS seized more than £300,000 of his assets including property, his BMW car and £20,000 in cash found inside.
A further £10,000 and a handgun and ammunition were found at Mr Owen's former marital home, which he regularly visited.
The police warned the public not to confront him.
Any information about the whereabouts of Andrew Rogers or Darren Owen can be passed on to a confidential appeals hotline on 0800 0855939.